The Public Service Railway, owned by the Public Service Corporation of New Jersey, operated most of the streetcar lines in New Jersey by the early 20th century. Public Service lines stretched from northeast New Jersey to Trenton, and then south to Camden and its suburbs. Major parts of the system were:
For many years, the only streetcar route still in operation was the #7 line, in the form of the Newark City Subway. The #7 at the turn of the 21st century underwent a line rehabilitation including new modern light rail cars, and was extended northward into Bloomfield. Additionally, a portion of an old NCS spur tunnel to the abandoned Cedar Street Subway (#13-Broad St., #27-Mt. Prospect, and #43-Jersey City), another Public Service trolley conduit, has been rehabilitated and opened for service in 2006 as another portion of the subway, to serve as a connection between Newark's two train stations and provide access to the Performing Arts Center, Newark Bears Stadium, Washington Park and the Newark Public Library. The other two light rail systems in New Jersey Hudson Bergen Light Rail and River Line are built along freight railroad rights-of-way and public streets, and do not date back to Public Service days.